 // 温度传感器代码如下

double Fahrenheit(double celsius)
{
return 1.8 * celsius + 32;
}    //摄氏温度度转化为华氏温度
 
double Kelvin(double celsius)
{
return celsius + 273.15;
}     //摄氏温度转化为开氏温度
 
// 露点（点在此温度时，空气饱和并产生露珠）
// 参考: http://wahiduddin.net/calc/density_algorithms.htm
double dewPoint(double celsius, double humidity)
{
double A0= 373.15/(273.15 + celsius);
double SUM = -7.90298 * (A0-1);
SUM += 5.02808 * log10(A0);
SUM += -1.3816e-7 * (pow(10, (11.344*(1-1/A0)))-1) ;
SUM += 8.1328e-3 * (pow(10,(-3.49149*(A0-1)))-1) ;
SUM += log10(1013.246);
double VP = pow(10, SUM-3) * humidity;
double T = log(VP/0.61078);   // temp var
return (241.88 * T) / (17.558-T);
}
 
// 快速计算露点，速度是5倍dewPoint()
// 参考: http://en.wikipedia.org/wiki/Dew_point
double dewPointFast(double celsius, double humidity)
{
double a = 17.271;
double b = 237.7;
double temp = (a * celsius) / (b + celsius) + log(humidity/100);
double Td = (b * temp) / (a - temp);
return Td;
}
 
#include <dht11.h>//程序中调用了dht11的库
 
dht11 DHT11;//定义一个名字叫做DHT11，类型为dht11的值。
 
#define DHT11PIN 2//定义DHT11的引脚号为D2。
 
void setup()
{
Serial.begin(9600);
Serial.println("DHT11 TEST PROGRAM ");
Serial.print("LIBRARY VERSION: ");
Serial.println(DHT11LIB_VERSION);
Serial.println();
}
 
void loop()
{
Serial.println("\n");
 
int chk = DHT11.read(DHT11PIN);
 
Serial.print("Read sensor: ");
switch (chk)
{
case DHTLIB_OK:
Serial.println("OK");
break;
case DHTLIB_ERROR_CHECKSUM:
Serial.println("Checksum error");
break;
case DHTLIB_ERROR_TIMEOUT:
Serial.println("Time out error");
break;
default:
Serial.println("Unknown error");
break;
}
 
Serial.print("Humidity (%): ");
Serial.println((float)DHT11.humidity, 2);
 
Serial.print("Temperature (oC): ");
Serial.println((float)DHT11.temperature, 2);
 
Serial.print("Temperature (oF): ");
Serial.println(Fahrenheit(DHT11.temperature), 2);
 
Serial.print("Temperature (K): ");
Serial.println(Kelvin(DHT11.temperature), 2);
 
Serial.print("Dew Point (oC): ");
Serial.println(dewPoint(DHT11.temperature, DHT11.humidity));
 
Serial.print("Dew PointFast (oC): ");
Serial.println(dewPointFast(DHT11.temperature, DHT11.humidity));
 
delay(2000);
}


//大气压传感器代码如下：
#include <Wire.h>
#include <SPI.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BMP280.h>

#define BMP_SCK 13
#define BMP_MISO 12
#define BMP_MOSI 11 
#define BMP_CS 10

Adafruit_BMP280 bme; // I2C
//Adafruit_BMP280 bme(BMP_CS); // hardware SPI
//Adafruit_BMP280 bme(BMP_CS, BMP_MOSI, BMP_MISO,  BMP_SCK);
  
void setup() {
  Serial.begin(9600);
  Serial.println(F("BMP280 test"));
  
  if (!bme.begin()) {  
    Serial.println("Could not find a valid BMP280 sensor, check wiring!");
    while (1);
  }
}
  
void loop() {
    Serial.print("Temperature = ");
    Serial.print(bme.readTemperature());
    Serial.println(" *C");
    
    Serial.print("Pressure = ");
    Serial.print(bme.readPressure());
    Serial.println(" Pa");

   // Serial.print("Approx altitude = ");
   // Serial.print(bme.readAltitude(1013.25)); // this should be adjusted to your local forcase
   // Serial.println(" m");
    
    Serial.println();
    delay(2000);
}